Dynamical entanglement of vibrations in the linear triatomic molecule by the algebraic approach

In this paper the dynamical entanglements of anharmonic vibrations in the linear triatomic molecules are researched by the Lie algebraic approach. The linear entropy and the Von Neumann entropy are analytically obtained for both initial Fock states and coherent states. The dynamical properties of entanglement in molecules HCN and DCN are discussed.